Current status of nutritional deficiencies in Canadian aboriginal people

Improved Retinol, Carotene, Ferritin, and Folate Status in Nuxalk Teenagers and Adults after a Health Promotion Programme

Plasma retinol and carotene, erythrocyte folate, serum ferritin, and haemoglobin were determined in native people living on the west coast of British Columbia before and after a three-year intervention programme of nutrition education and health promotion emphasizing local cultural food. One hundred ninety-nine persons participated before (T1) and 267 after (T2) the programme, with 107 persons participating in both periods. Overall T2 mean ± SEM adult (20–60 years) retinol increased (p <.05) over T1 from 23.8 ± 0.5 to 42.4 ± 17.3 μg/dl, carotene increased from 37.4 ± 1.2 to 54.1 ± 1.6 μg/dl, and erythrocyte folate increased from 226 ± 8 to 264 ± 8 ng/ml. T2 mean ± SEM adult ferritin and haemoglobin for all ages/sexes combined did not change; however, haemoglobin for older women 41 to 60 years of age increased (p <.05) from 12.4 ± 0.4 to 13.2 ± 0.2 g/dl, and the percentage of teenagers at risk for low ferritin levels was reduced for females from 85% to 17% and for males from 50% to 11%. It was concluded that the intervention programme improved vitamin A and folate status for the overall community and iron status for teenagers.

Red blood cell folate levels in Canadian Inuit women of childbearing years: influence of food security, body mass index, smoking, education, and vitamin use

Background

The benefits of folic acid for prevention of congenital anomalies are well known. For the Inuit of Canada, where vitamin use is low and access to folate-rich foods limited, fortification is likely a major source of intake. We sought to determine whether red blood cell folate (RBCF) levels of Inuit women reached accepted target levels.

Methods

The Inuit Health Survey, 2007–2008, included evaluation of RBCF levels among 249 randomly selected non-pregnant women of reproductive age. Using descriptive statistics and linear regression analyses, RBCF levels were assessed and compared across several socio-demographic variables to evaluate the characteristics associated with RBCF status.

Results

Mean (SD) RBCF levels of 935.5 nmol/L (± 192) reached proposed target levels (> 906 nmol/L); however, 47% of women had lower than target levels. In bivariate analysis, non-smoking, higher education, higher income, food security, increased body mass index, and vitamin use were each significantly associated with higher RBCF. Increased levels of smoking had a negative association with RBCF levels (− 5.8 nmol/L per cigarette smoked per day (p = 0.001)). A total of 6.8% of women reported taking vitamin supplements, resulting in a 226 nmol/L higher RBCF level on average compared to non-users (p < 0.001).

Conclusion

While mean levels of folate reached target levels, this was largely driven by the small number of women taking vitamin supplements. Our results suggest that folate status is often too low in Inuit women of childbearing years. Initiatives to improve food security, culturally relevant education on folate-rich traditional foods, vitamin supplements, and smoking cessation/reduction programs may benefit Inuit women and improve birth outcomes.

Prevalence of overweight and obesity among indigenous populations in Canada: A systematic review and meta-analysis

Previous studies on overweight and obesity among indigenous peoples in Canada have been inconclusive. A systematic review was conducted on the prevalence of overweight and obesity among Canadian indigenous populations. Major bibliographic databases were searched for relevant studies published between January 1990 and June 2013. We reviewed 594 abstracts and included 41 studies in the meta-analyses. Using the heterogeneity test (Cochrane Q) results, the overall prevalence was estimated using fixed- or random-effects model. Nonadults (<18 years) had a pooled prevalence of overweight and obesity at 29.8% (95% CI: 25.2-34.4) and 26.5% (95% CI: 21.8-31.3), respectively. The pooled prevalence of overweight and obesity among adults were 29.7% (95% CI: 28.2-31.2) and 36.6% (95% CI: 32.9-40.2), respectively. Adult males had higher overweight prevalence than females (34.6% vs. 26.6%), but lower obesity prevalence (31.6% vs. 40.6%). Nonadult girls had higher prevalence than boys [overweight: 27.6%; 95% CI: 22.6-32.7 vs. 24.7%; 95% CI: 19.0-30.5; obesity: 28.6%; 95% CI: 20.3-36.9 vs. 25.1%; 95% CI: 13.8-36.4]. Nonadult Inuit had the highest overweight and lowest obesity prevalence. Although Inuit adult had the lowest prevalence of overweight (28.7%; 95% CI: 27.3-30.2) and obesity (32.3%; 95% CI: 25.5-39.1), it was relatively high. This study highlights the need for nutritional intervention programs for obesity prevention among indigenous populations in Canada.

Disparity in cancer prevention and screening in aboriginal populations: recommendations for action

Historically, cancer has occurred at a lower rate in aboriginal populations; however, it is now dramatically increasing. Unless preventive measures are taken, cancer rates among aboriginal peoples are expected to soon surpass those in non-aboriginal populations. Because a large proportion of malignant disorders are preventable, primary prevention through socioeconomic interventions, environmental changes, and lifestyle modification might provide the best option for reducing the increasing burden of cancers. Such efforts can be further amplified by making use of effective cancer screening programs for early detection of cancers at their most treatable stage. However, compared with non-aboriginal Canadians, many aboriginal Canadians lack equal access to cancer screening and prevention programs. In this paper, we discuss disparities in cancer prevention and screening in aboriginal populations in Canada. We begin with the relevant definitions and a theoretical perspective of disparity in health care in aboriginal populations. A framework of health determinants is proposed to explain the pathways associated with an increased risk of cancer that are potentially avoidable. Major challenges and knowledge gaps in relation to cancer care for aboriginal populations are addressed, and we make recommendations to eliminate disparities in cancer control and prevention.

Country food sharing networks, household structure, and implications for understanding food insecurity in Arctic Canada

We examine the cultural context of food insecurity among Inuit in Ulukhaktok, Northwest Territories, Canada. An analysis of the social network of country food exchanges among 122 households in the settlement reveals that a household's betweenness centrality-a measure of brokerage-in the country food network is predicted by the age of the household. The households of married couples were better positioned within the sharing network than were the households of single females or single males. Households with an active hunter or elder were also better positioned in the network. The households of single men and women appear to experience limited access to country food, a considerable problem given the increasing number of single-adult households over time. We conclude that the differences between how single women and single men experience constrained access to country foods may partially account for previous findings that single women in arctic settlements appear to be at particular risk for food insecurity.

Severe vitamin D deficiency in 6 Canadian First Nation formula-fed infants

BACKGROUND

Rickets was first described in the 17th century and vitamin D deficiency was recognized as the underlying cause in the early 1900s. Despite this long history, vitamin D deficiency remains a significant health concern. Currently, vitamin D supplementation is recommended in Canada for breast fed infants. There are no recommendations for supplementation in formula-fed infants.

OBJECTIVE

The objective of this report is to bring attention to the risk of severe vitamin D deficiency in high risk, formula fed infants.

DESIGN

A retrospective chart review was used to create this clinical case series.

RESULTS

Severe vitamin D deficiency was diagnosed in six formula-fed infants over a two-and-a-half year period. All six infants presented with seizures and they resided in First Nation communities located at latitude 54 in the province of Manitoba. While these infants had several risk factors for vitamin D deficiency, they were all receiving cow's milk based formula supplemented with 400 IU/L of vitamin D.

CONCLUSION

This report suggests that current practice with regards to vitamin D supplementation may be inadequate, especially for high-risk infants. Health care professionals providing service to infants in a similar situation should be aware of this preventable condition. Hopefully this would contribute to its prevention, diagnosis and management.

Vitamin D in a northern Canadian first nation population: dietary intake, serum concentrations and functional gene polymorphisms

The wide spectrum of vitamin D activity has focused attention on its potential role in the elevated burden of disease in a northern Canadian First Nations (Dené) cohort. Vitamin D insufficiency, and gene polymorphisms in the vitamin D receptor (VDR) and vitamin D binding protein (VDBP) have been implicated in susceptibility to infectious and chronic diseases. The objectives of this study were to determine the contribution of vitamin D from food, and measure the serum concentrations of 25-hydroxyvitamin D(3) (25-OHD(3)) and VDBP in Dené participants. Single nucleotide polymorphisms (SNPs) associated with the dysregulation of the innate immune response were typed and counted. Potential correlations between the SNPs and serum concentrations of 25-OHD(3) and VDBP were evaluated. Venous blood was collected in summer and winter over a one-year period and analyzed for 25-OHD(3) and VDBP concentrations (N = 46). A questionnaire was administered to determine the amount of dietary vitamin D consumed. Sixty-one percent and 30% of the participants had 25-OHD(3) serum concentrations <75 nmol/L in the winter and summer respectively. Mean vitamin D binding protein concentrations were within the normal range in the winter but below normal in the summer. VDBP and VDR gene polymorphisms affect the bioavailability and regulation of 25-OHD(3). The Dené had a high frequency of the VDBP D432E-G allele (71%) and the Gc1 genotype (90%), associated with high concentrations of VDBP and a high binding affinity to 25-OHD(3). The Dené had a high frequency of VDR Fok1-f allele (82%), which has been associated with a down-regulated Th1 immune response. VDBP and VDR polymorphisms, and low winter 25-OHD(3) serum concentrations may be risk factors for infectious diseases and chronic conditions related to the dysregulation of the vitamin D pathway.

The development of a comprehensive maternal-child health information system for Nunavut-Nutaqqavut (Our Children)

OBJECTIVES

Nunavut is the most northerly jurisdiction in Canada of which 85% of inhabitants are Inuit. Although most infants are born healthy, Nunavut leads the country for adverse early child health outcomes such as infant mortality, rates of birth defects, prematurity and low birth weight. Public health and community efforts are needed to understand and improve outcomes.

METHODS

To inform these issues, a combined University of British Columbia/Nunavut Public Health Strategy effort has initiated a comprehensive maternal-child health surveillance system (from 16 weeks gestation to age 5). A diverse group of professional and lay stakeholders were brought together initially to determine local interest. Following this, a series of small working groups were held to decide on potential prenatal, perinatal and early child health variables, to be documented.

RESULTS

Over 100 Nunavut participants have now had some role in the development of the system which has been initiated. Pre-existing standard prenatal forms and well-child assessment forms have been modified to include "Nunavut specific" variables of nutrition, food and domestic security, exposures in pregnancy, birth defects, development, chronic diseases of childhood and paternal information.

CONCLUSION

This comprehensive maternal-child health information system has been developed with the extensive input of health care providers and stakeholders, utilizing community and public health systems already in place. Careful assessment of local needs has contributed to database development, privacy protection, potential data utilization for health promotion and plans for dissemination of findings. It is hoped that this will be a user-friendly surveillance system, adaptable to other community and public health systems that will improve the understanding of Aboriginal maternal-child health determinants.

Iron deficiency anemia among children: Addressing a global public health problem within a Canadian context

Despite current Canadian pre- and perinatal nutrition programs, the prevalence of both iron deficiency and iron deficiency anemia (IDA) is very high among young Aboriginal children from Canada's remote north. The major risk factors for IDA include prolonged consumption of evaporated cow's milk, chronic infection and prolonged exclusive breastfeeding. In the present article, the authors discuss IDA as a significant public health problem in Canadian Aboriginal communities. Whereas the prevalence of IDA in Canadian children is between 3.5% and 10.5% in the general population, in two Northern Ontario First Nations communities and one Inuit community, the anemia rate was 36%, with 56% having depleted iron stores. Traditional methods of preventing IDA, including targeted fortification, dietary diversification and supplementation, have not solved the problem. The authors' research group at The Hospital for Sick Children in Toronto, Ontario, conceived of the strategy of 'home fortification' with 'Sprinkles' - single-dose sachets containing micronutrients in a powder form, which are easily sprinkled onto any foods prepared in the household. In Sprinkles, the iron (ferrous fumarate) is encapsulated within a thin lipid layer to prevent the iron from interacting with food. Sprinkles have been shown to be efficacious in the treatment of anemia in many developing countries. Their use in Aboriginal communities to treat and prevent anemia is described in the present paper. The authors believe that children in Aboriginal communities across Canada would potentially benefit if Sprinkles were incorporated into Health Canada's current distribution system, in combination with a social marketing strategy to encourage their use.

Serum 25-hydroxyvitamin D is not associated with insulin resistance or beta cell function in Canadian Cree

Epidemiological studies report inverse associations between blood vitamin D, as measured by 25-hydroxyvitamin D [25(OH)D] concentrations, and insulin resistance (IR) among predominantly overweight individuals. In a cross-sectional survey of 5 Cree communities in Quebec, Canada, we determined if 25(OH)D is associated with IR and β-cell function in a largely obese, ethnic minority at high risk of developing type 2 diabetes. A total of 510 participants (≥18 y) without type 1 or type 2 diabetes, assessed for serum 25(OH)D, fasting plasma glucose and insulin, and anthropometric and lifestyle variables, were included in the analyses. Multivariable linear regressions adjusted for covariates were performed for homeostasis model assessment of IR (HOMA-IR) and β-cell function (HOMA-B) in relation to serum 25(OH)D. Serum 25(OH)D (per 10 nmol/L increment) was inversely associated with HOMA-IR (β = -0.005; SE = 0.002; P = 0.004) and HOMA-B (β = -0.004; SE = 0.002; P = 0.006) in models adjusted for age, sex, physical activity, education, alcohol consumption, and smoking. When further adjusted for BMI, associations were no longer significant for either HOMA-IR (β = 0.001, SE = 0.002, P = 0.572) or HOMA-B (β = 0.001, SE = 0.001, P = 0.498). The modest inverse associations between 25(OH)D and IR reported previously were not observed in this population after adjusting for adiposity. Future longitudinal studies investigating the interrelationship among 25(OH)D, adiposity, and the risk of developing metabolic syndrome and type 2 diabetes are warranted.

Vitamin D status of Inuit preschoolers reflects season and vitamin D intake

Rickets ascribed to hypovitaminosis D remains a public health concern among Aboriginal children in Canada and the United States. Our primary objective in this study was to investigate the prevalence and risk factors (gender, age, vitamin D intake, and socioeconomic status) for low vitamin D status of Inuit preschoolers living in 16 Arctic communities (51(o)N-70(o)N) and participating in the 2007-2008 Nunavut Child Inuit Health Survey. Children were selected randomly in summer (n = 282) and a follow-up was performed in winter for a subsample (n = 52). Dietary intake was assessed through the administration of a 24-h dietary recall and a FFQ. Anthropometric measurements (height, weight) were assessed. Plasma 25-hydroxy vitamin D was measured using a chemiluminescent assay (Liaison, Diasorin). Prevalence of vitamin D insufficiency (<75 nmol/L) among preschoolers was 78.6% and 96.8% in summer and winter, respectively. Median vitamin D concentrations and interquartile ranges in summer and winter were 48.3 (32.8-71.3) and 37.7 (21.4-52.0) nmol/L, respectively. The prevalence of vitamin D deficiency < 25 and < 37.5 nmol/L was 13.6 and 36.5%, respectively. Children who met or exceeded the adequate intake, those who consumed 2 or more milk servings (1 serving = 250 mL), and those who lived in households without crowding (47.7%) had a better vitamin D status than those who did not. The predictors of vitamin D status were dietary intake and age. Given low traditional food consumption and low consumption of milk, interventions promoting vitamin D supplementation may be required.

The paradox of anemia with high meat intake: a review of the multifactorial etiology of anemia in the Inuit of North America

Anemia is a serious concern among indigenous populations in North America, and it appears to be widespread among the Inuit despite abundant intakes of heme iron. It is therefore hypothesized that anemia for the Inuit involves other dietary factors not usually associated with animal foods, such as low intakes of vitamin A and/or folate, riboflavin, and vitamin C. Also, Helicobacter pylori infection and/or parasitosis may result in gastrointestinal blood loss and/or functional iron deficiency. This review aims to describe factors that may cause anemia in Inuit populations despite high meat intakes, abundant bioavailable iron, and other important hematological nutrients.

Vitamin D-deficiency rickets among children in Canada

BACKGROUND

Based on regional and anecdotal reports, there is concern that vitamin D-deficiency rickets is persistent in Canada despite guidelines for its prevention. We sought to determine the incidence and clinical characteristics of vitamin D-deficiency rickets among children living in Canada.

METHODS

A total of 2325 Canadian pediatricians were surveyed monthly from July 1, 2002, to June 30, 2004, through the Canadian Paediatric Surveillance Program to determine the incidence, geographic distribution and clinical profiles of confirmed cases of vitamin D-deficiency rickets. We calculated incidence rates based on the number of confirmed cases over the product of the length of the study period (2 years) and the estimates of the population by age group.

RESULTS

There were 104 confirmed cases of vitamin D- deficiency rickets during the study period. The overall annual incidence rate was 2.9 cases per 100,000. The incidence rates were highest among children residing in the the north (Yukon Territory, Northwest Territories and Nunavut). The mean age at diagnosis was 1.4 years (standard deviation [SD] 0.9, min-max 2 weeks-6.3 years). Sixty-eight children (65%) had lived in urban areas most of their lives, and 57 (55%) of the cases were identified in Ontario. Ninety-two (89%) of the children had intermediate or darker skin. Ninety-eight (94%) had been breast-fed, and 3 children (2.9%) had been fed standard infant formula. None of the breast-fed infants had received vitamin D supplementation according to current guidelines (400 IU/d). Maternal risk factors included limited sun exposure and a lack of vitamin D from diet or supplements during pregnancy and lactation. The majority of children showed clinically important morbidity at diagnosis, including hypocalcemic seizures (20 cases, 19%).

INTERPRETATION

Vitamin D-deficiency rickets is persistent in Canada, particularly among children who reside in the north and among infants with darker skin who are breast-fed without appropriate vitamin D supplementation. Since there were no reported cases of breast-fed children having received regular vitamin D (400 IU/d) from birth who developed rickets, the current guidelines for rickets prevention can be effective but are not being consistently implemented. The exception appears to be infants, including those fed standard infant formula, born to mothers with a profound vitamin D deficiency, in which case the current guidelines may not be adequate to rescue infants from the vitamin D-deficient state.

Nutritional concerns in aboriginal children are similar to those in non-aboriginal children in Prince Edward Island, Canada

OBJECTIVE

To assess food consumption among aboriginal children living on Mi'kmaq reserves in Prince Edward Island, Canada.

DESIGN

Data were collected as part of a larger study of health perceptions and behaviors in Mi'kmaq children and youth ages 1 to 18 years. Food consumption was assessed using a self-administered food frequency questionnaire during an in-home interview.

SUBJECTS/SETTING

Fifty-five children living on a reserve (53% of total population) ages 9 to 18 years.

STATISTICAL ANALYSES PERFORMED

The number of servings of milk products, vegetables and fruit, and snack foods/beverages was calculated by adding the responses to the frequency of consumption of foods assessed in each group. chi(2) analysis was used to assess differences in food consumption according to sex and age.

RESULTS

Only one child reported consuming the recommended minimum of five vegetables and fruit daily (Canada's Food Guide to Healthy Eating, 1992) (mean [+/-standard deviation]=2.8+/-1.1 servings). Twenty-five (49%) of the children consumed three or more servings of milk products daily (mean=2.6+/-1.3 servings). Approximately half of the children had three or more snack foods/beverages daily (mean=3.1+/-2.2 servings). Younger children (grades 4 to 6) consumed more cereal, peanut butter, and yogurt than older children. There were no significant differences in food consumption between boys and girls.

CONCLUSIONS

Our findings are consistent with past reports in aboriginal children. However, except for higher consumption of french fries, results are similar to recent surveys of other Prince Edward Island school children, suggesting a province-wide rather than cultural health issue.

Nutritional rickets around the world: causes and future directions

INTRODUCTION

Nutritional rickets has been described from at least 59 countries in the last 20 years. Its spectrum of causes differs in different regions of the world.

METHODS

We conducted a systematic review of articles on nutritional rickets from various geographical regions published in the last 20 years. We extracted information about the prevalence and causes of rickets.

RESULTS

Calcium deficiency is the major cause of rickets in Africa and some parts of tropical Asia, but is being recognised increasingly in other parts of the world. A resurgence of vitamin D deficiency has been observed in North America and Europe. Vitamin D-deficiency rickets usually presents in the 1st 18 months of life, whereas calcium deficiency typically presents after weaning and often after the 2nd year. Few studies of rickets in developing countries report values of 25(OH)D to permit distinguishing vitamin D from calcium deficiency.

CONCLUSIONS

Rickets exists along a spectrum ranging from isolated vitamin D deficiency to isolated calcium deficiency. Along the spectrum, it is likely that relative deficiencies of calcium and vitamin D interact with genetic and/or environmental factors to stimulate the development of rickets. Vitamin D supplementation alone might not prevent or treat rickets in populations with limited calcium intake.

Aboriginal status is a prognostic factor for mortality among antiretroviral naïve HIV-positive individuals first initiating HAART

Background

Although the impact of Aboriginal status on HIV incidence, HIV disease progression, and access to treatment has been investigated previously, little is known about the relationship between Aboriginal ethnicity and outcomes associated with highly active antiretroviral therapy (HAART). We undertook the present analysis to determine if Aboriginal and non-Aboriginal persons respond differently to HAART by measuring HIV plasma viral load response, CD4 cell response and time to all-cause mortality.

Methods

A population-based analysis of a cohort of antiretroviral therapy naïve HIV-positive Aboriginal men and women 18 years or older in British Columbia, Canada. Participants were antiretroviral therapy naïve, initiated triple combination therapy between August 1, 1996 and September 30, 1999. Participants had to complete a baseline questionnaire as well as have at least two follow-up CD4 and HIV plasma viral load measures. The primary endpoints were CD4 and HIV plasma viral load response and all cause mortality. Cox proportional hazards models were used to determine the association between Aboriginal status and CD4 cell response, HIV plasma viral load response and all-cause mortality while controlling for several confounder variables.

Results

A total of 622 participants met the study criteria. Aboriginal status was significantly associated with no AIDS diagnosis at baseline (p = 0.0296), having protease inhibitor in the first therapy (p = 0.0209), lower baseline HIV plasma viral load (p < 0.001), less experienced HIV physicians (P = 0.0133), history of IDU (p < 0.001), not completing high school (p = 0.0046), and an income of less than $10,000 per year (p = 0.0115). Cox proportional hazards models controlling for clinical characteristics found that Aboriginal status had an increased hazard of mortality (HR = 3.12, 95% CI: 1.77–5.48) but did not with HIV plasma viral load response (HR = 1.15, 95% CI: 0.89–1.48) or CD4 cell response (HR = 0.95, 95% CI: 0.73–1.23).

Conclusion

Our study demonstrates that HIV-infected Aboriginal persons accessing HAART had similar HIV treatment response as non-Aboriginal persons but have a shorter survival. This study highlights the need for continued research on medical interventions and behavioural changes among HIV-infected Aboriginal and other marginalized populations.

Review of vitamin D deficiency during pregnancy: who is affected?

OBJECTIVES

Vitamin D deficiencies have been documented in several populations, including aboriginal Canadians from isolated northern communities. Such deficiencies can impact the health of both the mother and her infant. This review was performed to determine how widespread vitamin deficiency is during pregnancy.

STUDY DESIGN

Electronic literature search.

METHODS

A Medline search was conducted using the Mesh terms "pregnancy" and "vitamin D". Those studies meeting the inclusion criteria were reviewed.

RESULTS

35 of 76 studies reported deficient mean, or median, concentrations of 25(OH)D. Low concentrations were reported among different ethnic groups around the world. In addition, deficient concentrations were identified in 3 northern First Nations communities in Manitoba.

CONCLUSIONS

Such deficiencies are of concern, as the developing fetus acquires its 25(OH)D across the placenta and may influence infant health. Future research is required to resolve the discourse surrounding ambiguous threshold values for vitamin D deficiencies and insufficiencies and to identify effective strategies to improve the vitamin D status of expectant women. Vitamin D supplementation may be necessary for many women during pregnancy, especially those in northern regions where endogenous synthesis may be constrained.

Biochemical Indicators of Nutritional Status and Dietary Intake in Costa Rican Cabécar Indian Adolescents

The purpose of this study was to determine the blood levels of selected nutritional status indicators and the dietary intake of Costa Rican Cabécar Indians aged 10 to 16 years. The results showed that 65% of the adolescents had an adequate body mass index (BMI) for their age, and 32% had a BMI < 5th percentile. Likewise, the study revealed a high prevalence of anemia (57%), deficient serum folate levels (54%), deficient vitamin B12 levels (31%), and subclinical vitamin A deficiency (10%). Additionally, the youngsters had elevated prevalences of high triglyceride levels (77%), borderline high-density lipoprotein (HDL) cholesterol levels (46%), homocysteine levels > 10 μmol/L (29%), and homozygous mutation of methylenetetrahydrofolate reductase (MTHFR) (49%). The diet was poor, being high in saturated fat and low in polyunsaturated fat, fiber, and several micronutrients. The dietary intakes of more than 55% of the adolescents did not meet 50% of the estimated average requirements (EAR) for zinc, vitamin A, vitamin C, vitamin B12, vitamin B2, and folate. Furthermore, a high prevalence of parasitosis was found (68%). Our results show an adolescent Cabécar population with a mosaic of nutritional deficiencies and cardiovascular risk factors.

Infection and anemia in Canadian aboriginal infants

The prevalence of anemia in Aboriginal children is high, but, given the high burden of infection in these children, the extent to which anemia is due to iron deficiency and/or infection is unclear. To determine the contribution of iron deficiency to anemia, we screened 144 Aboriginal infants (70 boys, 74 girls) who were free from infection. The prevalence of anemia (hemoglobin <105 g/L) was 18.8%; caregivers reported that 53.5% of infants had had an infection in the two weeks before screening. Anemic infants were more likely than non-anemic infants to have had an infection before screening (74.1% versus 48.7%, p = 0.02), and anemic infants had a higher prevalence of iron deficiency revealed by low serum iron concentrations (<7 micromol/L) (73.7% versus 38.3%, p <0.01). Iron deficiency measured using serum ferritin concentration tended to be less marked in infants who had had an infection (13% versus 30.3%, p = 0.06); this is probably because serum ferritin is a positive acute-phase protein. This study indicates the difficulty of isolating the contribution of infection to anemia from the separate effects of dietary iron deficiency.

Heart defects and other malformations in the Inuit in Canada: a baseline study

OBJECTIVES

Birth defects occur in all ethnic groups, remaining an important world-wide cause of perinatal and infant morbidity. This contributes greatly to an excess of health care dollars allocated to the care and repair of those affected. This is especially true when those affected live in remote geographical locations.

STUDY DESIGN

A chart review of 2567 live births of children of Inuit parents residing in Arctic Quebec (Nunavik) and on Baffin Island (Nunavut) between 1989 and 1994 (five years) was carried out compared to rates of anomalies of the Alberta Congenital Anomalies Surveillance System (ACASS).

RESULTS

Birth defects were higher in the Inuit sample in nearly every major ICD-9 category with the exception of neural tube defects, eye anomalies and chromosome abnormalities. (Total: 99.7/1000 Vs 51.5/1000; OR 1.93 95% CI 1.7-2.3). Congenital heart defects were significantly increased 22.9/1000 Vs 5.6/1000, with an OR of 4.18 (95% CI 3.2-5.4) in the ICD-9 category 745. In particular, ventricular septal defects (VSDs) and atrial septal defects (ASDs) (OR 4.9 CI 3.5-6.9 and 4.6 CI 2.9-7.2) were frequent.

CONCLUSIONS

A high rate of heart defects was an important contributor to the nearly two times rate of total birth defects in the Inuit compared to the ACASS. Further study should be carried out to determine the contributing factors. Genetic predisposition to specific heart defects, and a diet low in folate and vitamin A are considerations. The use of alcohol may exacerbate vitamin status in pregnancy. Optimizing vitamin status in the periconceptional period may reduce the rate of birth defects.

Maternal ethnicity and risk of neural tube defects: a population-based study

BACKGROUND

Maternal body mass and the presence of diabetes mellitus are probable risk factors for neural tube defects (NTDs). The association between maternal ethnicity and the risk of NTDs remains poorly understood, however.

METHODS

We performed a retrospective population-based study and included all women in Ontario who underwent antenatal maternal screening (MSS) at 15 to 20 weeks' gestation between 1994 and late 2000. Self-declared maternal date of birth, ethnicity and weight and the presence of pregestational diabetes mellitus were recorded in a standardized fashion on the MSS requisition sheet. NTDs were detected antenatally by ultrasonography or fetal autopsy and postnatally by considering all live and stillborn affected infants beyond 20 weeks' gestation. The risk of open NTD was evaluated across the 5 broad ethnic groups used for MSS, with white ethnicity as the referent.

RESULTS

Compared with white women (n = 290 799), women of First Nations origin (n = 1551) were at increased associated risk of an NTD-affected pregnancy (adjusted odds ratio [OR] 5.2, 95% confidence interval [CI] 2.1-12.9). Women of other ethnic origins were not at increased associated risk compared with white women (women of Asian origin [n = 75 590]: adjusted OR 0.9, 95% CI 0.6-1.3; black women [n = 25 966]: adjusted OR 0.6, 95% CI 0.3-1.1; women of "other" ethnic origin [n = 10 009]: adjusted OR 0.1, 95% CI 0.02-0.9).

INTERPRETATION

The associated risk of NTD-affected pregnancies was higher among women of First Nations origin than among women of other ethnic origins. The mechanisms for this discrepancy should be explored.

Prescription medications in Manitoba children: are there regional differences?

BACKGROUND

Population-based studies of pharmaceutical use in children provide information on disease prevalence, physician practice and adherence to treatment. We undertook an evaluation of regional differences in prescription drug use by Manitoba children.

METHODS

Using Manitoba's population-based prescription data for 1998/99, the prevalence of children receiving prescriptions for antibiotics, analgesics, iron supplements, and four classes of psychotropic drugs was reported for Regional Health Authorities and Winnipeg Community Areas, ranked by a measure of population healthiness, the premature mortality rate (PMR). Prevalence rates were also reported by census-based neighbourhood income areas.

RESULTS

60% of children received at least one prescription in 1998/99. Antibiotics, antiasthmatics, analgesics, antidepressants, and psychostimulants were the most commonly dispensed drugs. Prescription use of antibiotics, iron supplements, analgesics, antidepressants, antipsychotics and anxiolytics was highest in low income, urban neighbourhoods. Few associations between a region's PMR and prescription utilization were observed, but children living in regions with the least healthy populations were more likely to use antibiotics, non-steroidal anti-inflammatory drugs and anxiolytics. Psychostimulant use was unrelated to neighbourhood income, but highest rates were documented in some of the healthiest Winnipeg neighbourhoods.

CONCLUSION

We documented regional variation in prescription use which may be related to differences in health, physician practice or child use.

Exploring the determinants of health for First Nations peoples in Canada: can existing frameworks accommodate traditional activities?

While much research has examined First Nations peoples' health in Canada, few studies have explored the role of traditional activities in enhancing health. Using data from the 1991 Aboriginal Peoples Survey (APS), this paper incorporates a set of measures of traditional activities within a determinants of health framework for understanding First Nations peoples' health. Results from the analyses undertaken show that many of the determinants of health identified in analyses of the Canadian population in general hold for First Nations peoples. While only a few statistically significant relationships between health status and traditional activities were identified, taking into account the limitations of the APS and other conceptual issues, we argue that there is the potential to move from the analysis of traditional activities to a more nuanced analysis of cultural attachment.

Spina bifida, folate metabolism, and dietary folate intake in a Northern Canadian aboriginal population

OBJECTIVES

Inhabitants of the subarctic region of the Eastern James Bay of Northern Quebec consume a diet low in folate. This is largely secondary to poor access to plant-foods and a preferred diet high in meat, fowl, and fish as in many other northern populations. Furthermore, there is a high frequency of spina bifida in the Cree of the region. It was hypothesized that genetically altered folate metabolism as well as low folate intake contributes to the high frequency of spina bifida.

METHODS

A case-control study evaluating folate metabolism and the common 677C-T polymorphism of the gene for methylenetetrahydrofolate reductase (MTHFR) in mothers of children with spina bifida, and controls (n=23) of Cree descent from the Eastern James Bay region. These results were compared to a similar Montreal cohort (n=152) who were not of First Nations descent. Dietary intake of folate of 219 women of the Eastern James Bay region was also determined.

RESULTS

No Cree mothers of children with spina bifida were homozygous for the 677C-T polymorphism of MTHFR. Although serum cobalamin was significantly higher in Cree mothers, RBC folate was significantly lower than in the Montreal cohort. In addition, plasma homocysteine was significantly lower in the Cree. Dietary intake of folate of women in the same region was substantially lower (100 microg/day) than widely recommended daily intakes.

CONCLUSIONS

In this remote Canadian aboriginal community there is no evidence of altered folate metabolism in the mothers of children with spina bifida. Nonetheless, it remains essential that culturally appropriate public health efforts be continued to increase the intake of folic acid in the hope of reducing the high frequency of spina bifida in this population.

Blood lead concentrations and iron deficiency in Canadian aboriginal infants

Aboriginal Cree infants living in northern Quebec who were 9 months of age were screened for anemia, iron deficiency and elevated blood lead concentrations. Of the 314 infants who were eligible to participate, 274 (87.3%) were screened for anemia, 186 had blood lead concentration measured and 141 of the latter group had iron status determined. The median blood lead concentration was 0.08 micromol/l (range 0.01-1.00 micromol/l). The 25, 50 and 75 percentiles for blood lead concentration were 0.05, 0.08 and 0.12 micromol/l, respectively. The prevalence of elevated blood lead concentrations (> 0.48 micromol/l) was 2.7% (95% Cl 0.36-5.0). Among infants who had blood lead measured, the prevalence of anemia (hemoglobin < 110 g/l) was 25.0% and 7.9% of infants had iron-deficiency anemia (hemoglobin < 110 g/l and serum ferritin < 10 microg/l). Anemic infants had a higher mean geometric blood lead concentration than did babies without anemia (0.11 micromol/l vs. 0.07 micromol/l, P = 0.003). Likewise, infants with iron-deficiency anemia had a significantly higher mean geometric blood lead concentration than infants without iron deficiency anemia (0.16 micromol/l vs. 0.07 micromol/l, P = 0.001). There was a significant negative correlation between blood lead and hemoglobin concentrations (r = -0.203, P = 0.006) and between blood lead and serum ferritin concentrations (r = -0.245, P = 0.003). Infants who were fed traditional food (fish, fowl and game) did not have a significantly different mean geometric blood lead concentration, hemoglobin concentration or serum ferritin concentration than infants who did not eat traditional food. Few infants (5.3%) ate traditional food daily.

An iron treatment trial in an aboriginal community: improving non-adherence

OBJECTIVE

To compare supervised vs unsupervised oral iron treatment in anaemic Aboriginal children living in a remote community with a 40% prevalence of iron deficiency anaemia.

METHODOLOGY

A randomised unblinded clinical trial in children < 6 years presenting to a remote Health Centre with anaemia. Oral iron prescribed as a daily unsupervised dose (group A) was compared to twice weekly supervised administration (group B) over 12 weeks. Parenteral iron (group C) was reserved for failure of oral treatment.

RESULTS

Only 3 of 25 children in group A responded to treatment compared to 23 of 26 children in group B (odds ratio = 7.7, 95% confidence interval 2.6-25.0). After six weeks of treatment, the mean haemoglobin rise was 0.96 g/L in group A compared to 10.9 g/L in group B and 12.4 g/L in group C. On entry to the study, 29.4% of subjects were underweight, 33.3% stunted and 35.3% microcephalic. The mean catch-up in weight/height on iron treatment over the study was only 0.28 (0.08, 0.48) Z-scores.

CONCLUSIONS

Oral iron as directly observed twice weekly treatment is superior to unsupervised therapy. In view of the poor compliance with unsupervised treatment and the high prevalence of iron deficiency anaemia (along with stunting and microcephaly) in Aboriginal children in northern Australia, we propose to undertake in partnership with communities a nutritional intervention program with a high energy weaning food fortified with micronutrients (iron, vitamin A, zinc, folate) as the most effective strategy to address these nutritional problems in the weaning period.